Evolution of a ferrofluid floating layer under the influence of an inhomogeneous magnetic field

Abstract
In this paper, we investigate the influence of a vertically aligned magnetic field of a circular current loop on a ferrofluid layer located on a liquid substrate. It has been found that an increase in field strength leads to a threshold formation of the layer rupture in the form of a regular circle. The critical value of the field strength depends linearly on the initial layer thickness. The rupture initiated by the magnetic field does not disappear after removal of the field provided that the thickness of the ferrofluid layer is lower than the critical value. In the case of deformation of rather thick layers the occurrence of rupture is accompanied by the formation of well-ordered drop structures. Figs 6, Refs 3.